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We present test results on the use of thin ion implanted epitaxial Si detectors for registration of low- and medium-energy heavy fragments in nuclear reactions. A linear energy response for very low energy nuclei has been observed. A test of 10 μm + 300 μm telescopes under realistic experimental conditions for heavy ion experiments exhibits the possibilities to use these detectors for the measurements of multifragmentation products.

The silicon PN junction offers some advantages in contrast with ion chamber ; high quantum efficiency, very large dynamic range, good linearity, vacuum and cryogenically compatibility. This in particular in experiments using synchrotron radiation such EXAFS in absorption or in fluorescence mode. We use a 30 μm thin ion implanted and passivated silicon detector as a beam monitor and another planar diode of 200 μm to measure the photon flux behind the sample. These two detectors are working in the photovoltaic mode at room temperature. Currents are amplified in a low input impedance current preamplifier and are typically ten times greater than with an ion chamber for the same absorption. Thus the contribution of the electronic to the total noise is significantly less compared to the other system and faster rise time become possible. We have done in particular the copper foil EXAFS in 1 minute against 15 minutes in the conventional step by step mode.